Sirnaomics Ltd. — Share Issue/Capital Change 2025

Dec 7, 2025

Hong Kong Exchanges and Clearing Limited and The Stock Exchange of Hong Kong Limited take no responsibility for the contents of this announcement, make no representation as to its accuracy or completeness and expressly disclaim any liability whatsoever for any loss howsoever arising from or in reliance upon the whole or any part of the contents of this announcement.

Sirnaomics Ltd.

(Incorporated in the Cayman Islands with limited liability)

(Stock Code: 2257)

PARTIAL COMPLETION OF SUBSCRIPTION OF NEW SHARES UNDER GENERAL MANDATE AND TERMINATION OF SUBSCRIPTION AGREEMENT

Reference is made to the announcements of Sirnaomics Ltd. (the "Company") dated September 7, 2025 and September 17, 2025 (the "Announcements") in relation to the Subscriptions. Unless otherwise defined, capitalised terms used herein have the same meanings as defined in the Announcements.

PARTIAL COMPLETION OF THE SUBSCRIPTION AGREEMENT B

Partial completion of the Subscription Agreement B took place on December 7, 2025 and 1,003,700 new Shares were issued to the Subscriber B at HK12.00 per Subscription Share (the "Partial Completion").

After amicable negotiations in good faith, the Company and the Subscriber B mutually agreed that the subscription of the remaining 2,151,286 shares ("Remaining Shares") was terminated on December 7, 2025. Upon such termination, all rights and obligations of the parties shall cease to have effect and no party shall have any claim against each other in connection with the Subscription Agreement B. The Board considers that termination of the subscription of the Remaining Shares will not have any material adverse impact on the existing business, operational or financial conditions of the Company.

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EFFECT ON SHAREHOLDING STRUCTURE OF THE COMPANY

The following table shows the shareholding structure: (i) immediately before the Partial Completion; and (ii) immediately after the Partial Completion:

Shareholders	Immediately before the Partial Completion		Immediately after the Partial Completion
	No. of Shares	Approximate %	No. of Shares	Approximate %
Dr. Poon Hung Fai (Note 1)	17,527,696	16.50%	17,527,696	16.35%
Dr. Yang Lu (Note 2)	6,105,567	5.75%	6,105,567	5.69%
Mr. Mincong Huang (Note 3)	753,251	0.71%	753,251	0.70%
Subscriber B	—	—	1,003,700	0.94%
Subscriber D	1,051,662	0.99%	1,051,662	0.98%
Other public Shareholders	80,779,662	76.05%	80,779,662	75.34%
	106,217,838	100.00%	107,221,538	100.00%

Notes:

(1) Quarmaceutical Limited owns 17,527,696 Shares and Quarmaceutical Limited is wholly owned by Dr. Poon Hung Fai.

(2) Dr. Yang Lu ("Dr. Lu") is the settlor of The Yang Lu Family Trust and the beneficiaries of The Yang Lu Family Trust are Zheng Joan Wang and Laura Yao Lu, being Dr. Lu's spouse and daughter, respectively. Zheng Joan Wang and Laura Yao Lu are co-trustees of The Yang Lu Family Trust. Therefore, the co-trustees of The Yang Lu Family Trust are Dr. Lu's close associates. The above table shows Dr. Lu's shareholdings consisting of: (a) 2,500,000 Shares held by The Yang Lu Family Trust; and (b) 3,605,567 Shares beneficially owned by Dr. Lu. Dr. Lu resigned as a non-executive Director with effect from February 5, 2025.

(3) Huang Family Capital Ltd owns 198,950 Shares and Huang Family Capital Ltd is wholly owned by Mr. Mincong Huang ("Mr. Huang"). Mr. Huang also owns 554,301 Shares. Mr. Huang resigned as a non-executive Director with effect from January 1, 2025.

USE OF PROCEEDS

The net proceeds from the share subscription by the Subscriber B, after deducting the related expenses, are approximately HK$12.0 million. The Company intends to use the net proceeds for (i) the development and commercialization of STP705, (ii) the development of STP122G, (iii) the development of other drug candidates, including STP707, STP125G, (iv)

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business development activities to enrich the Group's pipeline and (v) general corporate and working capital purposes as disclosed in the announcement of the Company dated September 17, 2025.

TERMINATION OF SUBSCRIPTION AGREEMENT C

The Subscriber C was unable to perform its duties as set out under the Subscription Agreement C by December 7, 2025 and the Company has terminated the Subscription Agreement C in accordance with the provisions set out thereunder. Upon such termination, all rights and obligations of the parties shall cease to have effect and no party shall have any claim against each other in connection with the Subscription Agreement C. The Board considers that termination of the Subscription Agreement C will not have any material adverse impact on the existing business, operational or financial conditions of the Company.

By order of the Board

Sirnaomics Ltd.

Poon Hung Fai

Chairman and Executive Director

Hong Kong, December 7, 2025

As at the date of this announcement, the Board comprises Dr. Poon Hung Fai as executive Director, Mr. Ouyang Yunlong and Dr. Yin Huijun as non-executive Directors, and Mr. Wong Yu Shan Eugene, Dr. Zhang Peng and Ms. Lo Yee Hang as independent non-executive Directors.

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